1. while there isnot one standardnised technique,most dentist recommend a combination ofhoriontal and circular movements, lasting for between two to three minutes.
《lasting for between two to three minutes》是否目前分词作为定语修饰horiontal and circularmovements？
2. Fire-lighting wasrevolutionised by the discovery of phosphorus, isolated in 1669 by a Germanalchemist trying to transmute silver into gold.
《isolated in 1669 》是否过去分词作为定语修饰phosphorus？
以上两句为何可以是《逗号，+doing》或者《逗号，+done》作为定语分别修饰修饰movements和phosphorus？ 为何不是直接写《a combination of horiontaland circular movements lasting for 》和《the discovery of phosphorusisolated in 1669 》，movements和phosphorus作为先行词，他们不应是直接连着lasting和isolated的吗？目前用《逗号，》隔开，看着像是方法状语，但若是方法状语，他们的逻辑主语应该是dentist和Fire-lighting才对，但从句子翻译的意思来看，lasting和isolated就是修饰movements和phosphorus的。但这种《先行词+逗号，+doing》或者《先行词+逗号，+done》是否非常容易见到？
3、There are two steps to the occurrence of lightning from a cloud to the ground.这个《to the occurrence of lightning》是否也是to sth的介宾短语作定语修饰 steps? 还是说《to the occurrence of lightning》是介宾短语做补语修饰steps？？
【1】lasting for between two to three minutes. 被逗号隔开目前分词作定语，可以理解“非限制性定语从句”作定语。等于“which last for between two to three minutes”
【2】isolated in 1669 by a German alchemist trying to transmute silver into gold.. 被逗号隔开过去分词作定语，可以理解“非限制性被动语态定语从句”作定语。等于“which was isolated in 1669 by a German alchemist trying to transmute silver into gold.. ”
备注：没逗号隔开的“目前分词作定语或者过去分词作定语” 可以理解为“限制性定语从句”作定语。
【3】There are two steps to the occurrence of lightning from a cloud to the ground.
解答：“to the occurrence of lightning from a cloud to the ground” 为介词短语修饰前面名词“two steps”
